How Much Paint for a 12x16 Room?
Paint needed
2.5 gallons
A 12 by 16 room with eight foot walls, one door, two windows, two coats.
When the figures look right, the paint material list downloads as a real PDF with your business details on it, built inside your own browser. Nothing you type is uploaded anywhere.
How that number is worked out
These are the figures this page was built with and every line the calculator produces from them. Change anything above and all of it moves.
- Room perimeter, add all walls56 ft
- Wall height8 ft
- Doors1
- Windows2
- Coats2
- Coverage per gallon350 sq ft
Paint needed2.5 gallons
| Gross wall area | 448 sq ft |
|---|---|
| Less doors and windows | -51 sq ft |
| Net wall area | 397 sq ft |
| Area over 2 coats | 794 sq ft |
| Gallons, exact | 2.27 |
| Buy | 3 gallonsor 1 five gallon pail |
The material list this produces
| Paint, gallons | 3 |
|---|---|
| Primer, gallons (if bare or color change) | 2 |
| Painter's tape, rolls | 1 |
Coats compared
Coats is the input people get wrong, usually by hoping. Same room, one coat to three.
| Coats | Paint needed |
|---|---|
| 1 coat | 1.25 gallons |
| 2 coats | 2.5 gallons |
| 3 coats | 3.5 gallons |
What else matters here
Two and a half gallons is the worst possible answer, because paint is sold in gallons and five gallon pails and nothing in between that is worth buying. Three gallons it is, and you will have most of a gallon left.
At this size the five gallon pail starts to make sense if you are painting more than one room the same color. A pail is usually cheaper per gallon than four separate gallons, and it removes the other problem: four gallons mixed as four separate cans can vary slightly in shade, whereas a pail is one batch.
If you do buy individual gallons, box them. Pour all of them into a single larger container, stir, and pour back. It takes five minutes and it guarantees the last wall matches the first.
What this calculator assumes
- A door is taken as 21 sq ft and a window as 15 sq ft. Deducting them matters on a small room and barely moves a big one.
- 350 sq ft per gallon is the usual figure on a smooth primed wall. Bare drywall, textured walls and deep color changes all drink more, so drop it to 300 if any of those apply.
- Ceilings and trim are not included. Run the ceiling as its own area.
Questions people ask
How much paint for a 12x16 room?
About 2.5 gallons for two coats on eight foot walls, so buy three gallons. A five gallon pail is worth it if another room is getting the same color.
Why does the calculator say 2.5 gallons if I can only buy whole gallons?
So you can see how close to the line you are. At 2.5 you are buying three and have real spare. At 2.9 you are buying three and cutting it fine, which is worth knowing before the last wall.
What is boxing paint?
Mixing all your gallons together in one container before you start, then pouring back. It removes any shade difference between cans, which is the usual cause of one wall looking slightly off.
The paint calculator takes any dimensions you like and hands back the same list.